Problem with L6235 BLDC Motor Driver...

st05120171 · ‎2009-05-12

Posted on May 13, 2009 at 06:07

st05120171 · ‎2011-05-17

Posted on May 17, 2011 at 10:15

Hi,

I use L6235 brushless motor driver. I have a problem about controlling speed of my micro motor. I implement PWM in the Vref pin which before connected to an opamp and the tacho input.( as Vincenzo Marano explains in application note). I change PWM cycle but the speed of the motor doesn't change.

How can I change the speed of motor ?

And also some heating problem. Is there anyone to help me...

Thnks in advance

Celal

enrico-dora-spa · ‎2011-05-17

Posted on May 17, 2011 at 10:15

Hello,

you should check if VREF pin voltage varies with PWM as expected; as explained in AN, relation between PWM and VREF depends on low pass filter design.

You have to check if current control is properly working too.

Concerning heating problem, what are phase current and supply voltage values? What is the device package?

Systems using power devices as L6235 have to be careffuly designed from the power dissipation point of view (see power management paragraph).

If you could post more information we can try to solve the issue.

Regards,

Enrico Poli

Application Engineer - Motor control group